Robin Patenall

Science near Jool Having discussed it with Twilight, I okayed the mission to near Jool space with the restriction that nopony is to be on untethered EVA below 500km altitude, everypony must be in the engineering module or strapped into a command seat. This means no resetting of science experiments. Once given the go ahead, Twilight spared no time in grabbing Rainbow (apparently the great water landing debacle had been forgiven), getting in the lander and undocking. Rainbow plotted an ejection that would take them down and just scrap Jool’s upper atmosphere. Once done she’ll raise the periapsis slightly and wait a few orbits until they intersect Laythe again. Once they reached near Jool space, Twilight ran all the science experiments while Rainbow did crew reports. After they had finished, they were nearing the altitude at which Jool’s upper atmosphere starts so Twilight got strapped in and set up the experiments to run. After the lander’s altitude passed 500km, Twilight unstrapped herself and moved to the engineering module to pass a few days until they intersected Laythe’s SOI and Rainbow could show off by repeating Rarity’s aerobraking manoeuvre and redocking with the Emerald Star.

Squeezing out more Science Now that all the parts of the planned mission are complete and everypony is in one place, it is time to take stock of what resources we need to get home and what resources we have in addition to that. The first step was to reconfigure the Emerald Star for the return trip. The least obvious change was that the habitation module has been rotated to make ‘forward’ towards the drive truss, this allowed us to take the full drive core and move it into a position to push the habitation module home. All the LFO tanks on the emergency return capsules were topped off as were the LF tanks in the drive core. Some quick calculations show that we have plenty of fuel to get home, in fact we have just a shade under 8.6km/s. We could probably get home with half that amount and not be overly concerned. The remaining fuel comes to 5300 units of liquid fuel, 1423 of oxidizer and 1300 units of monoprop. This comes to enough to fuel the SSTO to design limits, the lander to about 2/3rds full and have enough liquid fuel in the last drive core to give it 2.5km/s of deltaV. I did do a bit more engineering work. I moved the telescope back to the science satellite and took the RCS thrusters that I originally took off the SSTO’s long range tanks and fitted them to the back of the drive core we’ve been using to ferry the lander about. We have massive amounts of monoprop on the drive truss, which we will be leaving here at Jool, and the drive core usually uses LFO for RCS which we have a limited amount remaining. Switching to monoprop (assuming the engineering module with its tanks is left attached) will allow more use out of it. We do need to decide if we use any of the resources we have left for more science. My thoughts were: Pol and Bop were studied pretty much completely by Rarity and Fluttryshy. Tylo is right out, we might be able to land but we’d never take off again and doing anything off equatorial, even in space, is probably beyond us. The SSTO can visit Laythe again but anything too inclined may be a problem and there isn’t much left on the equator unless we want to see if Rainbow Dash can launch from the ocean. We might be able (pulling some LFO from the return capsules) to return to Vall and land somewhere on the equator (specifically not he Vall henge site) So I’m off to see what Twilight thinks. Addendum Looks like Twilight had another idea. Use the current lander configuration and launch it toward retrograde to allow her to collect science from the space near Jool, that seems reasonable and doable, and she wants the periapsis to be low enough to scrape Jool’s atmosphere. That needs thinking about.

Pol Anomaly and Science Apparently, it’s not just Griffins that have eagle eyes. While helping Rarity with running the Pol science experiments, Fluttershy spotted the anomaly halfway up the mountain. If you have good eyes, you might be able to see it just above the top of Rarity’s helmet. Given the low gravity of Pol, it was at least conceivable that Rarity might be able to put the lander down on the side of the mountain but it wasn’t all that far, so Rarity hooked up the extra EVA fuel tanks to her EVA pack and just flew over there. When she arrived, she looked for a good landing point just up from the anomaly and found a very interesting rock sticking out from the ground that she could alight on. Well, Rarity found the anomaly, Rarity documented the anomaly, Rarity took samples from the anomaly and Rarity decided to otherwise ignore that the anomaly existed. Something I agree with. Once Rarity returned from the thing that she was pretending didn’t exist, she and Fluttershy took off and biome hopped to the nearby highlands and lowlands to check them out and then a longer hop to the north pole. Once they completed all the science on Pol, they took off and rendezvous with the drive core. Returning from Pol It turns out that both of our pilots are crazy. Once Rarity and Fluttershy had re-docked the lander to the drive core, they planned a reduced deltaV plan to arrive at Laythe using a gravity assist at Tylo to lose energy. Once they arrived at Laythe, Rarity did a burn at periapsis to capture into an elliptical orbit. It was at this point that Rarity showed her inner Rainbow Dash and decided to save some more detlaV by aerobraking using Laythe’s atmosphere. Now, she did this very carefully, taking many shallow passes and nothing showed anything other than slight temperature warnings. Admitally, I’d have preferred that the infrared telescope didn’t hang out in a plasma stream for a few minutes every hour or so for a couple of days, but it wasn’t needed anymore and it wasn’t damaged in any way. Eventually Rarity reduced the orbital apoapsis down to match the Emerald Star’s orbit and then raised the periapsis to rendezvous with it. The docking was rather tight and I’m glad that Rarity was piloting rather than Rainbow Dash. Rainbow would have managed the docking but I don’t know how long I would have had to be out on EVA touching up the paintwork. Even with Rarity in control, it was a tight squeeze.

Pol Landing About the time that Twilight started talking to Rainbow again, Rarity and Fluttershy arrived at Pol and put the lander and drive core into a polar orbit, allowing them to perform a full high survey. As the high orbital survey was concluding, the scanner picked up something strange. As no other place had been found that looked especially interesting, Rarity decided to make the, cheap, plane change to place the anomaly under the landers path while lowering the lander’s orbit for a low survey Once the low orbital survey was complete and the location of the anomaly was better identified, the lander was undocked and a descent was plotted that would put them reasonably close During the descent, Rarity couldn’t see anything unusual (unusual for Pol anyway) and she decided to prioritise a safe landing on the flat area in front of the large mountain over searching for the anomaly.

Laythe Landing 2 (and 3) The first thing that Rainbow and Twilight had to do was wait for almost a Laythe day to bring the anomaly under their orbit. Technically, this would happen after half a day, but that would mean that Rainbow would be landing in unknown terrain at night. Even she had enough sense not to do that if she didn’t have to. Unfortunately, Rainbow’s sense had run out and the aerocapture scare had been somewhat forgotten, so she decided to be helpful. Apparently, she saw a shallow inlet with gently sloped shores that was more or less, directly in her flight path, so she decided to give Twilight the chance to collect more data by landing the SSTO just off shore. I somewhat blame myself for this as we had told Rainbow that the SSTO was buoyant and that the engines would give her some thrust and manoeuvrability in the water and that in the event of a critical failure, shallow water might be the safest place to touch down if the land was problematic. We did not expect her to do it intentionally. After Twilight collected all the readings and samples she could before succumbing to sea-sickness, Rainbow successfully navigated the SSTO through the gaps in the sea ice and drove it up onto the shore. After Twilight’s dose of Dramamine had taken effect, she did another round of science tests, this time while they were landed on the shores rather than floating on the water above them. Once done, Rainbow took off again and flew the short distance to the anomaly that we had spotted from orbit. As the terrain by the anomaly was quite hilly and undulating, Rainbow overshot the target location a little so that she could land on a relatively smooth area, but even then she had to deploy the landing arrest parachutes. To save them from walking (the designers of our EVA suits were miracle workers but even they drew the line at wing sleeves, and Twilight had been told that teleporting was limited to a last resort measure), Rainbow taxied the SSTO back to where she had spotted the anomaly. I’m beginning to think that some higher power is messing with us. The skellington I’ll believe (especially after Fluttershy’s deep space kraken), but the potted plant? Twilight was happy though, I think that she might have been irritated if everybody but her had found something strange and interesting on the trip. (And now that I think about it, she took a cutting from the plant and brought it back with her… Let me check that she isn’t feeding it blood or anything) Take off and return to an equatorial orbit was no problem, between Laythe’s atmosphere and the SSTO’s powerful engines Rainbow managed to get the apoapsis into space with just the airbreathing jets. Matching the Emerald Star’s orbital plane and circularising left them with a significant amount of deltaV. Rendezvousing with the Emerald Star was a bit of a compromise. We lowered the Star’s apoapsis to 440km and did the final manoeuvres with the SSTO. This left the Emerald Star in a better orbit for final departure but didn’t use as much fuel as moving to a fully circular orbit would take. Apparently Twilight was prudent enough to not start shouting at Rainbow about her stunt with the water landing until they had left Laythe and docked. I eventually had to send them to separate corners. Rainbow is sulking in one of the emergency return pods and, given that we don’t have a library, Twilight is checking off lists in the lab.

Science Satellite Retrieval While Rainbow Dash and Twilight were playing Antarctic explorers, we decided to pick up the science satellite that we sent through Jool’s upper atmosphere. It was in nearly the same orbit as the Emerald Star, but it still needed over 300m/s of dV as we needed to change the argument of periapsis A bit of orbital work and the satellite was docked to the Emerald Star and it’s precious data and atmospheric samples from Jool safely stored. Breaking News! While we’ve been orbiting Laythe, we’ve also been scanning the ground and our sensors have detected some sort of anomaly. It’s even on the equator, so it’s a perfect target for Rainbow Dash and Twilight to land at. In other news, it seems that the user interface for Kerbnet was written by griffons; I’ll submit a bug report that the anomaly icon needs to be bigger so people without eagle eyes can actually see it.

Laythe Landing 1 After a half dozen simulated runs at the south pole, where nobody died, I gave Rainbow the okay to ask Twilight if she’d like to add a stop to the mission to get some more scientific information. Obviously, she said yes. So Rainbow undocked from the long range tanks and brought up the flight controls and plotted an atmospheric entry that would put the SSTO down at a latitude of -87 degrees, close to the pole. She also brought up the science controls for Twilight so she could make measurements as they passed through the lower atmosphere. A retrograde burn pushed the SSTO into the atmosphere where it started to aerobraking. Rainbow was right about how smooth the polar regions are, so the touchdown and coming to a halt were anticlimactic. They planted a flag, and took some public relations photos of them in the land of Perpetual Twilight. Once Perpetual Twilight had exhausted all the experiments she could do and safely stored the results, she and Rainbow got back on board and waited for the long range fuel tanks to pass overhead, so she could take off. As Laythe had rotated, the orbit of the fuel tanks had shifted relative to the ground. If the SSTO had been near the equator it would have taken half a Laythe day (7h 20m ish) for the orbit to be close but near the poles it was just a slight change in heading. Once in a stable orbit, Rainbow plotted a rendezvous with the long range tanks. When she finally docked, Rainbow Dash refilled all the tanks on the SSTO to design limits and it looks like there are 400 units of LFO remaining in the long range tanks (with about 60 units of extra fuel). When undocked from the SSTO this will give the tanks about 1000m/s of dV which will be used to push them into a higher orbit where they can act as a communication satellite.

Rainbow’s bright idea It looks like while I was moving the Emerald Star, Rainbow Dash has been thinking, and while normally that’s cause for concern, it looks like her scare with the aerocapture has made her re-evaluate a bit. It seems that she might have designed a sensible mission expansion that we can do with resources that would only be wasted and is actually well thought out. She noticed that the remaining fuel and oxidizer left in the SSTO’s long range tanks, which at this point is going to be wasted in Laythe low polar orbit, is almost enough to refill the SSTO back to the design levels. There are only about 180 units of liquid fuel missing and the SSTO, designed for Kerbin, tends to have some left over after landing and returning to Laythe orbit, so long as the pilot doesn’t fly around too much. So her idea was that, given some constraints, she might be able to land the SSTO, take off, rendezvous with the long range tanks, refuel and then go on to perform the primary mission. The two biggest constraints were that: She needed a landing point where she could safely brake to a stop without using the emergency arrest parachutes as she would not be able to repack them. This means nice and flat. She wouldn’t be able to fly around too much as she needs to conserve fuel. So the landing point needs to be a big target. Turns out that Rainbow Dash noticed that the Laythe polar ice caps are, like home, as flat as a pancake. A perfect landing spot. She even selected the South pole as it would mean that the sun would be behind her, instead of in her eyes, and that her overrun, if landing in sunlight, is more polar icecap, not the ocean. All pluses. I’ve set up some simulated missions based on this using the SSTO’s cockpit flight computer and if she can complete them, without stranding herself, I’ll give her provisional approval to raise the idea with Twilight (who is the mission specialise for Laythe and will have the final say) Note: Rainbow jumped on the sim and on her first attempt managed to re-dock with the tanks, refuel the SSTO and leave the tanks with about 700m/s of dV (when not playing tug to the SSTO) so they can raise their orbit to over 1000km and act as an additional relay. It looks like a go…

Moving the Star to Laythe Absolutely nothing exciting. A very small burn to leave Vall SOI at the right time brought the Emerald Star’s periapsis down to Laythe’s orbit. A couple of loops brought us to Laythe and another small burn to capture in an elliptical orbit. All told less than 100m/s of dV (which would have been done with the fuel I couldn’t take off the SSTO) I did get some nice pictures. Once before we left and one once we captured.

Laythe Aerocapture Yes, “aerocapture” no “aerobrake”. My original mission plan had Rainbow doing an engine burn at a Laythe periapsis of 90km and then, if Rainbow was confident, use aerobraking to lower the apoapsis. The idea was to progressively increase the depth that the SSTO went into the atmosphere so we could gauge how safe it was. Rainbow’s mission plan was to throw all that out of the airlock, say hold my cider, and perform an aerocapture to save fuel. To her credit, Rainbow realised that she’d bucked up and contacted me on Kerbnet almost the instant they were out of the atmosphere. She was very contrite, and having downloaded the logs and reviewed them, I see why. The large docking port on the long range fuel tanks had come a hair’s breadth away from a critical overheat, losing that probably wouldn’t have caused an instability but having bits of your ship explode is never good. I got Twilight out on EVA to inspect the science bay (she was raring to go do that anyway, I don’t think she understood what almost happened) and spent ten minutes informing Rainbow, in excruciating detail, how she and Twilight almost had a Bad Day. Rainbow promised that the aerobraking manoeuvres to circularise the orbit would be much shallower and they were. It took almost three days to bring the orbit down to 121km by 90km giving Twilight plenty of opportunities to get readings from high space, low space and the upper atmosphere. In fact that went so well that we skipped circularising in a high space orbit as virtually all the readings had been made. (There are some tiny island biomes which hitting from orbit would be a million-to-one shot)

Arrival and landing at Bop While Rainbow and Twilight were starting on their way to Laythe, Rarity and Fluttershy had reached Bop, going into a circular polar orbit to allow them to do a full survey of the moon. This didn’t take too long as Bop is a small moon and once finished, Fluttershy had identified five different types of area that she wanted to look at. Rarity, as the pilot, had a reasonable idea about the total resource limit of the mission and with a few hours of mission simulation she’d been able to tell Fluttershy, Bop’s mission specialist) that they should be able to land in all five area types, but there was a hard cut off on fuel and if they reached it the mission the the surface was over. The first landing zone was on a tall peak near the north pole, which was in sunlight and they would then work their way south toward a large valley near the equator, so when they reached position, they undocked from the drive core and when for a landing The mission hiccup (because every mission seems to need one) came not long after Rarity lifted off from their first landing. Reviewing the logs, Fluttershy said “Oh, that poor thing”, switched her pilot controls to main and executed a barely controlled burn at almost right angles to prograde. Once Rarity had cut Fluttershy out of the command loop and regained control she decided to set down and, in looking for the nearest sensible place to land, she saw what Fluttershy had seen. Just to be clear: It’s dead They’ve taken lots of photos and samples. I spent way too long playing Kerbnet ping-pong between Twilight and the Bop team. I walked Rarity through setting up quarantined storage for the samples on the lander. We already have one Emerald Star (because Laythe) and nobody is touching the samples until we get back home. The Emerald Star is just not equipped for that level of research. It took far too long for Rarity to convince Fluttershy that they weren’t in a position to bury it. Once they finished examining the remains, Rarity was able to pilot the lander to four other spots on Bop and allowed Fluttershy to collect samples and readings. According to Rarity it wasn’t that interesting (“It’s a brown rock. It’s rocky and brown”) but Fluttershy was diligent. Once all the samples and reading had been taken, Rarity put the lander in orbit, matched planes with the drive core and redocked. A course for Pol orbit, starting in a few days has been plotted.

Launching the Spaceplane to Laythe One of the problems we had while planning this mission was attempting to put vessels into polar orbits of the inner three moons to get as much scientific information that we could. But we found that, due to the small distance between them, it was easier to do an inclination change at the edge of thee moons SOI so the Laythe space plane was fitted with external fuel tanks that would give it the deltaV to make this plane change and circularise around Laythe. However, having had some practical experience with gravity assists in the Jool system, I was able to plot a set of manoeuvres that would take the spaceplane out past the orbit of Tylo, then flyby Tylo to slow down and adjust its inclination to arrive at Laythe in a polar orbit and do thing using much less fuel than the brute force solution. Before Rainbow Dash and Twilight left in the spaceplane, I removed some of the struts (those that would be exposed during an aerobrake manoeuvre) and some of the RCS as the plane would not be performing RCS translation in one piece any more. As we’d be using less deltaV, I attempted to remove as much fuel as I could from the plane’s tanks as I could, pumping into the Emerald Star’s tanks, but there just wasn’t enough space for it all. If I’d thought about it before Rarity left with the Bop / Pol lander, I could have put some there but it looks like we might need to dump (or at least waste) the extra fuel. Once we reached the departure point, Rainbow Dash and Twilight boarded the spaceplane and made the first burn of that twelve day journey. Once they arrive I’ll take what’s left of the Emerald Star on a much less costly route to Laythe equatorial orbit

Yeah... I suspect you're right. I checked and didn't see much about using EVA construction at all (I suppose it's quite recent ). It's for a mission, specifically it's my Laythe SSTO with it's extended fuel tanks. Basically, I did Tylo and Vall, then sent the Vall lander with one of my main drive cores off to do Bop / Pol and rendezvous with the main ship, travelling separately, in a Laythe parking orbit. This needs about 2km/s of dV to push the lander about and the drive, with just the lander on it, was ludicrously over powered, so I pumped out as much fuel to the main ship as I could (it still has > 5km/s). Then I looked at taking the main ship and SSTO to Laythe where I wanted the SSTO in polar orbit (for science reasons) and the main ship in equatorial orbit (for getting back to Kerbin easily reasons). During my planning I couldn't find a decent way of doing this without brute forcing the inclination change at the edge of Laythe's SOI and, because I was also skittish about circularising via aerobreak, I gave the SSTO extended tanks with >1000m/s of dV to do both manoeuvres. Except I don't need it. I've found a gravity assist (thanks Tylo) that massively reduces the cost of the inclination change and I am feeling much more confident about the aerobreak, so if I wanted to reduce the fuel levels so I don't leave as much in a useless polar orbit and might use for another Vall biome or Laythe landing. But, no room... Actually getting rid of it is easy, I have drain valves I can fit during EVA, but throwing away fuel... Honestly, I'm being silly about it. I way overspec'ed the ship, the bits of my mother-ship that need to go back to Kerbin should have >5km/s of dV while waiting for a transfer window in the Laythe parking orbit.

Quick question, does anybody know if using a mod like KSP_PartVolume to make more parts available to be moved using EVA construction would make the attempt a MODDED one? I've got myself in a corner where I'm going to have to throw away fuel because I'm separating a lander and I don't have enough tank space on the mother ship to remove the excess fuel and save it (I think I have way too much fuel but throwing it away goes against the grain). I thought I could rearrange some tanks via EVA construction, but I've been playing with KSP_PartVolume too long and forgot that none of the 2.5m tanks (specifically the Rockomax X200-8 Fuel Tank) can be affected by an engineer. I'd like not to throw away fuel, but I'd prefer not to have a MODDED entry when I don't need to.

Science Satellite Flyby Once I managed to turn the satellite’s engines around and out a bit of fuel in it (it’s very light so it didn’t need much) we waited until the ejection time, undocked it and executed a burn to have it fly by Laythe After using Laythe to slow down, we collected science from space low about Jool and dipped, ever so slightly, into Jool’s upper atmosphere to collect samples and other readings. By the way, if anybody asks, we absolutely did not hear somebody saying "My god, it's full of stars" while doing this. Once out of the atmosphere, we were able to plot a manoeuvre at apoapsis to raise the periapsis and put the satellite on course for an orbit of Laythe, So we have a special science present to open once we get there.

Science Satellite With Rarity and Fluttershy off to the outer moons, we have some down time. We’re not sure yet if we will wait here at Vall for them to return or whether we’ll move onto Laythe and rendezvous with them there, the decision will probably have to wait until they are ready to leave Pol so we can compare fuel usage. Bon Bon managed to avoid Twilight for a day before the Purple Pony of Perspicacity grabbed her and proceeded to interrogate her about everything she’d seen and done on the surface of Vall. Don’t worry, if I don’t see them in a day or two, I’ll go rescue her. With Rainbow keeping a low profile in the Laythe plane, I’ve had some time to look at the science satellite. The plan was to send it through the upper layers of Jool’s atmosphere to collect data and even without its gravioli detector this can still work, we even might be able to get the experiments run in low Jool space if the lander meets us in Laythe orbit. The only issue we might have is control as the relay satellites have not moved into their correct positions yet, we still have dead spots. Let me check the numbers… It looks like we have a lucky alignment. In two days there is a course that will eject from our Vall orbit, fly by Laythe to lose energy, scrape Jool’s atmosphere and intersect again with Laythe, where the satellite could wait in orbit for us. Even the relay satellites are pretty much in the best position for control during the dive and the return to Laythe. I might want to do an EVA and turn the engines over before we launch it though. It’s designed to fly through the atmosphere with the fuel tank forward, acting as a sort of heat shield, and with the engines as they are we can’t boost the satellite’s speed without bringing the instruments into the airstream. Turning the engines around will allow us to command a burn to offset the drag losses without changing the satellite’s attitude.

Preparations for Pol and Bop Once the lander was back, we cleared out the science and refuelled it for Rarity’s and Fluttershy’s mission to the outer moons Pol and Bop. We are carrying extra oxidizer onboard so they can refuel the lander while they are out there to give them the mission flexibility to attempt multiple landings if they find anything interesting during the orbital surveys that they will do. Hopefully they’ll bring some back as the oxidizer level is beginning to become something of a concern, nothing critical but it could reduce our ability to be flexible in our options. I did move the telescope from the science satellite as it will be able to get observational data from Pol and Bop, and Fluttershy had collected all the science that it could generate from around Vall while Twilight was distracted by what was happening on the surface. After checking the positions of the moons, it turned out that there was a good transfer to Bop coming up in a couple of orbits, so after some final checks, Rarity and Fluttershy undocked from the Emerald Star and performed an ejection manoeuvre.

Vall landing Well, they found it. It took several days of orbital surveying, and an altitude change, but Bon Bon and Rarity found Twilight’s anomaly. It’s about 60 degrees South of Vall’s equator, so we’d never have seen it if we weren't specifically looking for it. They completed the orbital survey and waited until the anomaly's location passed under the lander’s orbit on the daylight side of Vall. They then left my engineering module, boarded the lander and undocked. Rarity managed a pinpoint landing, with the anomaly only being a short walk away (in fact any closer and she might have landed on it). I wanted the team to do the planned science experiments first and load them into the experiment containers before going to poke the ancient alien artefact, but I was overruled. Apparently, pointing out if they did the experiments first and the artefact ate them, I’d be able to remote pilot the lander back and we wouldn’t have wasted a landing just got me the stink eye. Between getting photos of every square inch of the site and Twilight wanting Bon Bon and Rarity to run every experiment she could think of that they could with the limited resources of the lander we did manage to get the planned science done. In fact both of the team made their own discoveries. Bon Boon noticed a cryo-volcano not too far away and managed to carve out a few hours to study it and Rarity’s gem finding spell is apparently one of more generic set of ‘find a valuable thing’ spell and she managed to find a scientifically important ice chunk. (Exactly why this chunk of ice is more important than all the others is beyond me but Bon Bon was ecstatic with Rarity’s find) By the time that Twilight had exhausted every bit of scientific data that the team could wring out of the artefact, the sun had set and the lander was in a poor position to rendezvous with the drive core, so Bon Boon and Rarity got some rest until Vall put them under the orbit again. They re-docked the lander to the dive core and returned to the Emerald Star by raising their apiosis, undoing the plane change and entering into a phasing orbit.

Vall orbital survey Looks like we have a small change of plan. Once I got Twilight calmed down, it turned out that, during our close approach to Vall, something on the surface triggered her thaumometer. She wasn’t very clear what she actually measured (thaums, apparently, I’m an engineer not a unicorn) but when translated from EggHead it looks like there is something on Vall that is emitting or reacting to magic in a way that is not natural. The only things we know are that this is one of the greatest magical discoveries in a millennium, and whatever it is is not on the equator. That last point was a bit of a problem as the plan for Vall was to bring the Emerald Star into an equatorial circular orbit (200 to 300km), find a good spot for landing then detach the lander from the mothership to land, do all the surface science then ascend back into orbit and redock with us. This would have limited our landing spot to within a few degrees of the equator. However, we did have some excess fuel. Not that any space mission has fuel to waste, but our transfer from Tylo to Vall took less fuel than we had budgeted so we had some leeway to use a bit more if we have a reason to do so. The new plan was that we’ll do more or less what we did at Tylo. We’ll detach a drive core and join it to the lander and my engineering module (so that Bon Bon and Rarity have some living space). You can see this on the left side of this image. This wasn’t an untested configuration, as it is the same setup that we’d be sending to Pol and Bop next, so this was just setting it up early and having Rarity test it before doing a long range mission was a good idea. This then executed a 90 degree plane change at apoapsis and circularized its orbit of Vall to a 95km polar orbit. Bon Bon (Vall mission specialist) and Rarity (Pilot) will now make a full survey of Vall from orbit looking for Twilight’s magical anomaly. If they find it they can then use that they are in a polar orbit to target it as the landing spot. This mission will only take about 500m/s of deltaV more out of the drive core than the original plan. As we aren’t moving the whole ship, this may consume about the same amount of fuel. The only issue I had with this change in plan was I had to endure Twilight’s repeated attempts to go down to the surface of Vall. Unfortunately, the lander only seats two and Twilight can’t replace either of the planned crew. Bon Bon is the mission specialist for Vall and we need her expertise in exo-glaciology on the surface and Twilight isn’t qualified to pilot (anything… ever…) so she can’t replace Rarity.

Finishing up Tylo After the Tylo landing, we had two things to finish up before we left Tylo. First, Fluttershy spent some time in the lander using the refitted negative gravioli detector to finish up the experiments that Bon Bon couldn’t. We also launched the relay satellites, these will give us better coverage as we explore the rest of Jool’s moons. They will eventually end up in a 85Mm orbit about Jool, the first is almost there, there’s just a bit of fine tuning with the RCS thrusters to do. The others are one their way and will enter an 85Mm by 80Mm phasing orbit to position them at approximately 120 degree intervals. Once all the satellites were launched I rebalanced the Emerald Star by adjusting the fuel loads on the tanks to reduce the torque generated by the engines. As it turns out, the next periapsis was a perfect time to eject from Tylo to be moving retrograde with respect to its orbit and bring us down to Vall. There were some issues with us catching Tylo up and potentially reentering its SOI but we eventually managed to thread the needle and arrive at Vall. We are currently in an elliptical equatorial orbit, like we were at Tylo, of 2Mm by 73km and we’ll be able to plan out our work here with this as a starting point, but that may have to wait as Twilight is bouncing of the walls of the lab shouting stuff in the language of EggHead.

Where are my spares! I went to replace the second barometer with a negative gravioli detector from my spares and they’re not here! All I found was a Post-it note reminding somebody to schedule the launch of the space instruments. We should have had five aboard (lander, Lythe plane, science satellite and two spares) and we have two. I took the one off the science satellite and swapped it for the extra barometer, we should be fine so long as we are careful in planning… but Arggg!

I did the first landing of my Jool 5 mission on Tylo (to dump the weight of the Tylo descent stage). (Yes, they're not kerbals. As I have to be careful to put the right crew on the right missions to the right moons, I wanted to be able to distinguish them easily by sight) My only issue was that I accidently added two barometers rather than a barometer and a negative gravioli detector. I'll manage to get all the other readings but will have lost the landed at Tylo one as they're not comming back.

Tylo Landing As our orbit around was taking us up to apoapsis we decided to prepare the ship for the landing on Tylo. As it would take almost 800m/s of deltaV to change from our highly elliptical orbit to the 50km circular orbit that the Tylo lander was designed for, the plan was to use the virtually empty drive core that we expended getting here to take the lander down and refuel the ascent stage on the way back up. This would leave the drive core in Low Tylo orbit. Getting this all together required us to rearrange the Emerald Star to get the lander out and to disconnect the central drive core. You can see the Laythe plane on the dorsal habitation docking node and the lander and drive core on the ventral. Once we reached apoapsis, the lander undocked and adjusted it’s periapsis to 50km. Over the next few orbits, the drive core reduced the lander’s orbit to a 50kkm circular orbit, where it parked so that the lander’s ascent stage could dock with it to refuel for the rendezvous with the Emerald Star. Rainbow Dash and Bon Bon spent some orbits waiting for the target landing zone to be in the daylight by taking some measurements from low orbit. This could be done from the Emerald Start but it would take longer as the measurements could only be taken when near Tylo. One problem that they did discover was that they did not have a negative gravioli detector, but two barometers. Practical upshot, we’ll have to make these measurements from the main ship and we’ll lose the measurement from the surface, but I’ll swap it out from my spares once they arrive back. Once the landing site was in daylight, Rainbow Dash piloted thee lander down. Rainbow didn’t get the landing perfect, a few hundred meters further on was flatter but we forgive her as there was a significant amount of fuel left in the descent stage. They spent some time doing the flag planting thing, the tourist thing and the science thing. As Rainbow had managed to save a significant amount of fuel in the descent stage, she used it to give the ascent stage an initial boost as there was no point leaving there on the surface. She then brought the ascent stage into a 50km by 20km orbit, matched inclination with the drive core and slowly caught up with it and docked. (ignore the deltaV readouts, something gone wrong, the ascent stage has over 3000m/s fully fuelled) After refuelling the ascent stage, the drive core had just enough deltaV to palace it (and the ascent stage) into a 500km by 50km orbit. The would give the ascent stage a boost and would mean that the drive core would cycle between low and high space. It’s start tracking cameras are great as scientific but with the comms array and the RCS fuel remaining, I’m sure that the KSC will manage to put it to use. The lander was placed on a phased rendezvous orbit with the Emerald Star and Rainbow docked it back. All the science was offloaded and it was refuelled ready for its next use as the Vall lander.

Arrival at Tylo About fifty three days after we reached Jool’s SOI we did a Tylo fly by to slow ourselves and capture at Jool. We didn’t do any science experiments as we passed as we would be back soon and could take our time then. A couple of small correction manoeuvres were planned that would bring us back to Tylo after a fly by of Vall and a third manoeuvre to get a very loose capture at Tylo. The total delta V for whole capture is less than 300m/s. A quick fly by of Vall… … and capture around Tylo We are now in a very loose orbit of Tylo with a periapsis of 90km and apoapsis of 10Mm.

Arrival at Jool We’ve eventually arrived at the outskirts of Jool. We still have a huge distance to go (about 2.5 billion meters in fact) to get there, but our travel time is measured in tens of days rather than years. You might not be able to see it but there is a tiny green smudge just off the front of the Emerald Star in the image, that’s Jool. Twilight has eventually been allowed to run science experiments (“At last!”) and she went on an EVA to collect them from the instruments aboard the science satellite and perform some other experiments herself that she could do while out there. We actually run each experiment three times, twice to be returned to Kerbin and once so that Twilight and the other scientists can analyse the data in the mobile processing lab (having nothing to do with what we’re afraid would happen if Twilight got bored) We also made a tiny correction burn to improve our fly past of Tylo, shortening the resultant orbit and putting us on course for a Val encounter, which will allow us to further adjust our orbit.